replace subshell with command chain

automated install/basic-install.sh

@@ -135,8 +135,8 @@ fi
 is_repo() {
   # Use git to check if directory is currently under VCS, return the value
   local directory="${1}"
-  (cd ${directory} && git status --short) &> /dev/null
-  return
+  curdir=$PWD; cd $directory; git status --short &> /dev/null; rc=$?; cd $curdir
+  return $rc
 }
 
 make_repo() {